Question about an ingredient in HC-110?

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There was an interesting article on HC-110 called the unofficial HC-110 guide:

http://www.covingtoninnovations.com/hc110/

In one point in reading about the compsoed components of the solution, there is a chemical called pentetic acid which is a chelating agent in removing most of the physical minerals that may be in regular water. I'm wondering if anyone knows how much of an amount this chemical works in doing this type of job? This is an interesting article to read.

-- Robert D. (rjphoto120@aol.com), June 14, 2001

Answers

This is indeed an interesting article and answers many of the questions regarding HC-110 that have been asked recently. I have been going back through old negatives to find developing times that worked in the past, and note that some of the sharpest 35mm negatives I ever made were developed in HC-110. I always had trouble with that damn thick syrup, but Mr. Covington gives some interesting methods for dealing with it, and states that it isn't as thick as it used to be. I do remember getting blocked-up highlights sometimes, but I never experimented with anything other than dilution B.

-- Ed Buffaloe (edb@unblinkingeye.com), June 15, 2001.

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